Advances in mass spectrometry have provided unprecedented opportunities for the analysis of proteins, such as peptide internal sequencing, post-translational modification, non-covalent interaction, and protein folding. Here we request funds to purchase an integrated TheroFinnigan LCQ DECA-10000/LC Packings Ultimate LC/MS/MS system that will allow the research communities at the University of Medicine and Dentistry of New Jersey-New Jersey Medical School and Rutgers University-Newark to take advantage of this state-of-the-art technology in protein research. Currently, there is no instrument available that allows researchers at either institute to sequence and elucidate protein structures using tandem mass spectrometry. Provision of this technology will significantly enhance the quality and productivity of the research on both campuses. We have assembled a group of NIH-funded investigators plus 7 other researchers frm 7 departments at both universities whose research would be significantly enhanced by the availability of this integrated system to our New Jersey Medical School-RUTGERS University, Newark (NJMS- RUN) Mass Spectrometry Core Facility. The projects outlined in this application entail basic research into the structure and function of proteins from a wide-range of organisms-human, yeast and bacteria. The research fields that will be served are equally broad and include protein identification, nuclear protein complex identification, protein-ligand interaction, quality control of designer metallo-protein synthesis and post-translational modification of proteins. This equipment will be located in our Mass Spectrometry Core Facility laboratory. It will be supervised and maintained by Dr. Hong Li, an experienced mass spectrometrist who is in charge of the facility. Two committees drawn from both institutions oversee the fiscal and scientific management and daily operation of this facility. The service provided by this facility has met with overwhelming demand. The addition of the integrated ThermoFinnigan LCQ DECA-10000/LC Packings Ultimate LC/MC/MS system will complement our existing MALDI-TOF instrument, permitting the facility to cover most of our mass spectrometry needs.